Center punch micrometer



United States Patent 3,293,763 CENTER PUNCH MICROMETER Edward J. Stell, 5613 W. 12th St., Sioux Falls, 5. Dak. 57001 Filed Aug. 27, 1964, Ser. No. 392,549 3 Claims. (Cl. 33--191) My invention relates to a micrometer or diameter measuring device associated with a center punch arrangement.

An object of my invention is to provide a micrometer which can be used to readily measure the correct diameter of a round bar, and which will also include an auxiliary attachment whereby the center of the bar will be pre-sct, and so that the center can be punched by the usual punching tool.

A further object of my invention is to provide a device which will firmly clamp the arrangement, and wherein the auxiliary device can be quickly set in correct position.

With these and other objects in view, my invention consists in the construction, arrangement, and combination of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

FIGURE 1 is a plan view of the device,

FIGURE 2 is a side View, and

FIGURE 3 is an enlarged sectional detail taken along the line 3-3 of FIGURE 1.

I have used the character to designate a bar or strap upon which the inch indicating marks 11 are marked thereon, together with fractions of an inch, this bar including the lengthened slot 12, and attached at one end of the bar 10 is the arcuate member 13. The bar 10 slides within a further member 14 having an opening at 15, and also having a further arcuate member 16 attached thereto, and also formed integrally with the member 14 are the side flanges 17, and passing through the flanges 17 is a stud 18 having the tightening nut 19 threadably engaged therewith for suitably clamping the member 14 to the member 10 when desired.

Extending from the member 14 and attached thereto at 20 is the small circular collar 21 through which passes the cylindrical member 22 which is attached to the knurled portions 23, to assist in rolling the member 14 along the edge of the member 10, since the knurled portions 23 will permit the thumb of the operator to roll the members 23 which will roll along the edge at 11.

The character 24 indicates a further bar which is also attached to the arcuate member 16 and attached at one end of the bar 24 is the vertically positioned flange 25, the bar 24 also including a slot at 26.

Threadably engaging the flange 25 is the lengthened threaded rod 27 having the thumb screw 28 attached thereto and at the end thereof for rotating the bar 27, a further tightening thumb screw being indicated by the character 29. The threaded rod 27 is rotatably secured at 30 to a vertical flange 31 which is formed integrally with the punch member 32, the member 32 including a punch receiving opening 33, the member 32 also including a small pointer 33a adapted to register with the inch, etc. marks 34 which are provided on the bar 24. The markings 34 are preferably made exactly one-half in dimension of the markings 11 on the member 10, so that when the diameter of the bar to be measured is determined and set, the operator can set the point 33a on the same marking, which will provide a more accurate centering for the punch and at the same time provide a convenient method whereby the operator will not need to divide the full dimension of the bar by 2. The member 32 can include an integral expanded portion 35 (see FIGURE 3) which will slide within a corresponding groove 36 provided in the member 24 to provide greater stability to the member 32.

In using the device, the arcuate member 16 is placed against the round bar indicated by dotted lines character 37 and the arcuate member 13 is moved to engage the bar 37, and then the nut 19 is tightened which will securely attach the arrangement. Next, the thumb nut 28 is rotated until the indicator 33a rests upon the same diameter marking, and then the nut 29 is rotated to bear against the flange 25 which will thereby lock the arrangement and then a standard punch tool is passed through the opening 33, through the slots 12 and 26 and the punch marking is then made.

It will now be noted that I have provided the various advantages mentioned in the objects of my invention with further advantages being apparent.

Some changes may be made in the construction and arrangement of the parts of my invention without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

I claim as my invention:

1. A center punch micrometer comprising a fixed bar, a further movable bar slidably engaged with said fixed bar, an arcuate member attached to said fixed bar, a further arcuate member attached to said further movable bar, means for moving said further movable bar with respect to said fixed bar, said further movable bar having diameter indicating markings on one edge thereof, said fixed bar having center punch indicating markings thereon, a punch guide member slidably engaged with said further movable bar and having a pointer adapted to register with any of the markings on said fixed bar, means for moving said punch guide member along said further movable bar.

2. A center punch micrometer comprising a fixed bar, a further movable bar slidably engaged with said fixed bar, an arcuate member attached to said fixed bar, a further arcuate member attached to said further movable bar, means for moving said further movable bar with respect to said fixed bar, said further movable bar having diameter indicating markings on one edge thereof, said fixed bar having center punch indicating markings thereon, a punch guide member slidably engaged with said further movable bar and having a pointer adapted to register with any of the markings on said fixed bar, means for moving said punch guide member along said further movable bar, including a lengthened threaded stud rotatably secured to said center guide punch member, said further movable bar including a flange threadably engaging said lengthened stud.

3. A center punch micrometer comprising a fixed bar, a further movable bar slidably engaged with said fixed bar, an arcuate member attached to said fixed bar, a further arcuate member attached to said further movable bar, means for moving said further movable bar with respect to said fixed bar, said further movable bar having diameter indicating markings on one edge thereof, said fixed bar having center punch indicating markings thereon, a punch guide member slidably engaged with said further movable bar and having a pointer adapted to register with any of the markings on said fixed bar, means for moving said punch guide member along said further movable bar, including a lengthened threaded stud rotatably secured to said center guide punch member, said further movable bar including a flange threadably engaging said lengthened stud, means for tightly securing said bar to said further bar after a pre-determined diameter has been set, an indicator connected to said arcuate member for indicating on said further movable bar markings the corresponding diameter of a member to be measured, the markings on said fixed bar being onehalf the spacing on the markings on said further movable bar to thereby indicate to an operator the center point of said member to be measured corresponding directly to the' LEONARD FORMAN, Primary Examiner.

WILLIAM D. MARTIN, IR., Assistant Examiner. 

1. A CENTER PUNCH MICROMETER COMPRISING A FIXED BAR, A FURTHER MOVABLE BAR SLIDABLY ENGAGED WITH SAID FIXED BAR, AN ARCUATE MEMBER ATTACED TO SAID FIXED BAR, A FURTHER ARCUATE MEMBER ATTACHED TO SAID FURTHER MOVABLE BAR, MEANS FOR MOVING SAID FURTHER MOVABLE BAR WITH RESPECT TO SAID FIXED BAR, SAID FURTHER MOVABLE BAR HAVING DIAMETER INDICATING MARKINGS ON ONE EDGE THEREOF, SAID FIXED BAR HAVING CENTER PUNCH INDICATING MARKINGS THEREON, A PUNCH GUIDE MEMBER SLIDABLY ENGAGED WITH SAID FURTHER MOVABLE BAR AND HAVING A POINTER ADAPTED TO REGISTER WITH ANY OF THE MARKINGS ON SAID FIXED BAR, MEANS FOR MOVING SAID PUNCH GUIDE MEMBER ALONG SAID FURTHER MOVABLE BAR. 